+
+ if (side_data_size && additional_id == 1) {
+ block_additions = start_ebml_master(pb, MATROSKA_ID_BLOCKADDITIONS, 0);
+ block_more = start_ebml_master(pb, MATROSKA_ID_BLOCKMORE, 0);
+ put_ebml_uint(pb, MATROSKA_ID_BLOCKADDID, 1);
+ put_ebml_id(pb, MATROSKA_ID_BLOCKADDITIONAL);
+ put_ebml_num(pb, side_data_size, 0);
+ avio_write(pb, side_data, side_data_size);
+ end_ebml_master(pb, block_more);
+ end_ebml_master(pb, block_additions);
+ end_ebml_master(pb, block_group);
+ }